The world is unprepared for a massive virus outbreak, the deputy chief of the World Health Organisation warned on Tuesday, amid fears that H7N9 bird flu striking China could morph into a form that spreads easily among people.

No new human cases of the H7N9 virus have been recorded in China for a week, national health authorities said, for the first time since the outbreak began in March.

One previously infected patient died in the week beginning between May 13, the National Health and Family Planning Commission said in a statement late on Monday, taking the total number of fatalities from the virus to 36.

All live chicken in Hong Kong – including those being raised locally or imported from the mainland on a daily basis – should undergo the test before being sold to consumers, the health minister said on Monday.

A Sars-like virus that has struck in Britain and the Middle East has claimed a new victim in Saudi Arabia, bringing the global toll from the mystery illness to nine, the World Health Organisation said on Tuesday.

British officials say a mysterious virus related to Sars may have spread between humans, as they confirmed the 11th case worldwide of the new coronavirus in a patient who they say probably caught it from a family member.